The present invention, as exemplified by the present disclosure, relates generally to a manually actuated pump dispenser for a liquid product. While the viscosity of an acceptable liquid product for use in the disclosed pump dispenser may extend over a fairly wide range, one of the more important properties or characteristics is that the liquid product have a viscosity so as to be flowable through the corresponding pump mechanism. Some of the fluid products which are considered suitable to be dispensed by the disclosed pump dispenser structure include hand and body lotions, shower gels, liquid soap, food condiments, flavorings and syrups.
One of the concerns with liquid products of the type mentioned above is the potential for a residue remainder to be left in the vicinity of the exit passageway, upstream from the outlet opening of the nozzle, as well as being left in and around the outlet opening of the nozzle. This residue remainder, over time, loses some of its moisture content and typically becomes a gummy layer or glob which remains in the nozzle of the dispenser even during subsequent dispensing strokes for the delivery of additional product.
When a residue builds up at and around the edge of the outlet opening of the nozzle, it is likely that the size of the outlet opening will be reduced and what was a generally circular or cylindrical exit opening now has an irregular edge. One possible result or outcome from the reduced size of the opening due to a gummy residue build up is a higher velocity stream for the exiting product. A smaller stream of exiting product is usually associated with this higher velocity. Another possible result or outcome from this build up is an exiting stream of product which is misdirected, or off-axis due to the irregular edge profile. A higher exit velocity and a dispensing direction which is not only off-axis, but is also random and unpredictable, are disadvantages in almost any setting where dispensers of this type will be used and are disadvantages for almost of any type of product.
It would therefore be an improvement to the type of pump dispensers being discussed herein if the residue remainder could be managed and controlled so as to lessen the likelihood of a residue buildup around the outlet opening of the nozzle. Even if the buildup of a gummy residue within the nozzle cannot be prevented in its entirety, it would still be an improvement to slow down the rate of residue buildup. A further improvement would be to limit the majority of any residue buildup to less critical portions of the nozzle, such as in the exit passageway, upstream from the outlet opening.
The present invention, as exemplified by the present disclosure, addresses the residue buildup issue by the addition of a weir which is placed at a location upstream from the outlet opening of the nozzle. Related to the use of a weir is the overall nozzle shape and geometry. The weir is part of a unitary plastic molding and its presence does not directly impact any other features or components of the pump dispenser in a way which would warrant any modification to the current or existing construction. The desired valving, plunger, piston and cylinder of the pump dispenser, for example, are unaffected by the addition of the weir. Further, the body of the nozzle is constructed and arranged with an incline or inclined shape relative to the plunger axis so that any product which might remain in or around the outlet opening of the nozzle drains back into the exit passageway, away from the outlet opening. Even if some gummy residue might remain in the nozzle, keeping it away from the outlet opening is one of the keys so that there is less or minimal concern about an unacceptable exit velocity and less or minimal concern about any “misdirected” off-axis stream of product as it leaves the outlet opening.